Unless compatibility with gpg is a requirement, I think scrypt[0] is a much simpler tool for file encryption. The utility is meant to showcase the KDF of the same name. It's very simple and has virtually no parameters. So:

  $ xz -k elrond_minutes.txt
  $ scrypt enc elrond_minutes.txt.xz elrond_minutes.txt.xz.enc
  $ signify -S \
      -s vilya.key \
      -m elrond_minutes.txt.xz.enc \
      -x elrond_minutes.txt.xz.enc.sig
  $ rm elrond_minutes.txt{,.xz}

Signing the final output is probably extraneous; I think scrypt uses a HMAC. This involves invoking multiple tools, but since each tool only does one thing it's much easier to reason about, and I prefer this over using an omnibus tool like gpg.

[0] https://github.com/Tarsnap/scrypt